Polymer electrolyte fuel cell

Abstract

For a combination of a solid polymer electrolyte membrane 107 , catalytic layers 111 and 113 disposed on both sides of the solid polymer electrolyte membrane 107 , gas diffusion layers 112 and 114 disposed outside the catalytic layers 111 and 113 , and separators 103 and 104 disposed outside the gas diffusion layers 112 and 114 , the catalytic layer 113 to be cathode-sided includes a carbon carrier 117 composed of carbon having a mean lattice plane spacing d 002 of [002] planes calculated from an X-ray diffraction within a range of 0.343 nm to 0.358 nm, a crystallite size Lc within a range of 3 nm to 10 nm, and a specific surface area within a range of 200 m 2 /g to 300 m 2 /g, catalyst particles 115 containing platinum supported on the carbon carrier 117 , and an electrolyte 116 . According to the invention, a polymer electrolyte fuel cell is allowed to prevent a corroding deterioration of carbon carriers in the cathode catalytic layer in start and stop of the fuel cell, allowing for an enhanced stable output over a long term.

1. A polymer electrolyte fuel cell, comprising:
 a solid polymer electrolyte membrane; 
 catalytic layers disposed on both sides of the solid polymer electrolyte membrane; 
 gas diffusion layers disposed outside the catalytic layers; and 
 separators disposed outside the gas diffusion layers, 
 wherein a cathode-sided catalytic layer of the catalytic layers comprises:
 a carbon carrier comprising carbon having a mean lattice plane spacing d002 of [002] planes calculated from an X-ray diffraction within a range of 0.343 nm to 0.358 nm, a crystallite size Lc within a range of 3 nm to 10 nm; 
 catalyst particles containing platinum supported on the carbon carrier; 
 and an electrolyte, 
 wherein the carbon carrier comprises a carbon black having a bulk density within a range of 0.09 g/cm3 to 0.13 g/cm3; 
 wherein the carbon black has an electrical resistivity within a range of 0.27 Ωcm to 0.33 Ωcm. 
 
 
     
     
       2. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein the carbon carrier comprises an acetylene black having a mean lattice plane spacing d 002  of [002] planes calculated from an X-ray diffraction within a range of 0.343 nm to 0.355 nm, a crystallite size Lc within a range of 3 nm to 9 nm, a bulk density within a range of 0.10 g/cm 3  to 0.12 g/cm 3 , and an electrical resistivity within a range of 0.29 Ωcm to 0.32 Ωcm. 
     
     
       3. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein the catalyst particles occupy a proportion within a range of 30% to 70% in a mass conversion with respect to a total amount of the catalyst particles and the carbon carriers residing in the cathode catalytic layer, and the catalyst particle-supporting carbon carrier has a specific surface area within a range of 60 m 2 /g to 200 m 2 /g. 
     
     
       4. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein the electrolyte in the cathode-sided catalytic layer and the solid polymer electrolyte membrane comprise perfluorocarbon polymers having sulfonic acid groups. 
     
     
       5. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein the cathode-sided catalytic layer has an average thickness ranging 6 μm to 15 μm, and the catalyst particle-supporting carbon carrier has a proportion of existence within a range of 50% to 80% with respect to a total mass in which the electrolyte and the catalyst particle-supporting carbon carrier are summed up. 
     
     
       6. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein, for an anode side, the catalytic layer has an average thickness ranging 2 μm to 10 μm, and the catalyst particle-supporting carbon carrier has a proportion of existence within a range of 50% to 80% with respect to a total mass in which the electrolyte and the catalyst particle-supporting carbon carrier are summed up. 
     
     
       7. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein, for an anode side, the catalytic layer has an average thickness Ya thinner than an average thickness Yc of the cathode-sided catalytic layer. 
     
     
       8. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein, for an anode side, the catalytic layer has an average thickness Ya with a relationship of Ya/Yc=0.1 to 0.6 to an average thickness Yc of the cathode-sided catalytic layer. 
     
     
       9. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein the catalyst particles comprise a platinum alloy containing a metal selected from the group consisting of ruthenium, rhodium, palladium, iridium, osmium, chromium, cobalt, and nickel. 
     
     
       10. The polymer electrolyte fuel cell as claimed in  claim 9 , wherein the platinum alloy has a mixing ratio (platinum/metal) of platinum and the metal ranging 3/1 to 5/1 in a mole ratio. 
     
     
       11. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein, for an anode side, the catalytic layer comprises a carbon carrier having a specific surface area within a range of 300 m 2 /g to 1,500 m 2 /g, catalyst particles containing platinum supported on the carbon carrier, and an electrolyte. 
     
     
       12. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein the cathode-sided catalytic layer comprises a first catalytic layer and a second catalytic layer, and carbon carriers in the second catalytic layer have a higher anti-corrosiveness in comparison with carbon carriers in the first catalytic layer neighboring the solid polymer electrolyte membrane. 
     
     
       13. The polymer electrolyte fuel cell as claimed in  claim 12 , wherein an electrolyte in the second catalytic layer has a greater ion exchange capacity in comparison with an electrolyte in the first catalytic layer. 
     
     
       14. The polymer electrolyte fuel cell as claimed in  claim 12 , wherein the second catalytic layer has a greater support amount of the catalyst particles therein in comparison with a support amount of the catalyst particles in the first catalytic layer. 
     
     
       15. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein a double-layered catalytic layer of the cathode-sided catalytic layer is disposed in a region opposing a vicinity of an upstream of a fuel gas. 
     
     
       16. The polymer electrolyte fuel cell as claimed in  claim 1 , wherein a double-layered catalytic layer of the cathode-sided catalytic layer is disposed in a downstream region of an oxidant gas.